地质学报2016，Vol.90Issue(2)：341-351,11.
藏北商旭金矿床 S、Pb 同位素组成：对成矿物质来源的指示
Sulfur and Lead Isotope Compositions of the Shangxu Orogenic Gold Deposit in Northern Tibet:Implication for the Source of Ore-forming Material
摘要
Abstract
The Shangxu orogenic gold deposit locates to the south of the middle part of the Bangong-Nujiang suture zone in northern Tibet.Four stages of mineralization were identified,which are quartz stage (S1), quartz-pyrite stage (S2 ),quartz-polysulfide stage (S3 )and carbonate stage (S4 ).Furthermore,the precipitation of gold mainly occurs in S2 and S3.The wall rocks of the deposit are the Middle-Lower Jurassic metamorphic flysh Mugagangri Group.The sulfides in S3 has a narrowδ34 S range of -4.5‰ to-1.0‰ with an average of - 3.1‰,which is consistent with the δ34 S of pyrite from the wall rocks, indicating sulfur mainly derived from the metamorphic flysh Mugagangri Group.The δ34 S values of S3 satisfyδ34 SGn <δ34 SSp ,representing the outcome of sulfur isotopic thermodynamic equilibrium fractionation;meantime,the temperature is 197 ℃ according to sphalerite-galena sulfur isotopic thermodynamic equilibrium.Three samples from S3 yield 206 Pb/204 Pb values of 18.35 ~ 18.69 and 207 Pb/204 Pb values of 15.64~15.70,and 208 Pb/204 Pb values of 38.57 ~38.98;theμvalues vary from 9.55 to 9.63,while the ωvalues vary from 37.75 to 38.15,indicating that the lead source was highly mature and derived from the upper crust,maybe including the contribution of melange in orogenic belts.关键词
硫同位素/铅同位素/造山型金矿/班公湖-怒江缝合带/西藏/商旭Key words
sulfur isotope/lead isotope/orogenic gold deposit/Bangong-Nujiang suture zone/Tibet/Shangxu引用本文复制引用
裴英茹,杨竹森,赵晓燕,张雄,马旺,徐玉涛,毛敬涛..藏北商旭金矿床 S、Pb 同位素组成：对成矿物质来源的指示[J].地质学报,2016,90(2):341-351,11.基金项目
本文为国家重点基础研究发展计划（973计划）（编号2011CB403104）、地调项目子课题（编号12120113037901）及国际海域资源调查与开发“十二五”课题（编号 DY125-12-R-01）联合资助的成果。 （）
